NEW YORK — On his way back to the locker room at Arthur Ashe Stadium, Denis Shapovalov dropped his bags on the court to stop and thank the crowd. He patted his heart and blew kisses to the fans who were giving him a standing ovation.

Although he was frustrated by the mental errors he made in a 7-6 (2), 7-6 (4), 7-6 (3) loss to Spain’s Pablo Carreno Busta in the fourth round of the U.S. Open on Sunday, Shapovalov said that thanking the fans for their support has been his favourite moment in a whirlwind month.

The defeat — where he pushed the 12th-seeded Carreno Busta to three tiebreaks — ended the deepest run the 18-year old from Richmond Hill, Ont., had ever embarked upon in a senior Grand Slam tournament. It came four weeks after he upset some of the biggest names in tennis at the Rogers Cup in Montreal.

“It was so much fun to be part of that atmosphere in the match,” said Shapovalov, who had to win three qualifying matches to make the main draw of the Grand Slam event. “This whole two weeks, it’s another life-changing event for me. It’s all thanks to the crowd. They’ve been having my back these past couple of months and they’ve really been carrying me.

“Without them, surely enough, this wouldn’t have been possible.”

Denis Shapovalov returns to Pablo Carreno Busta at the U.S. Open on Sept. 3.Clive Brunskill /
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Shapovalov had a career breakthrough at the Rogers Cup, where he was entered as a wild card. In Montreal he defeated world No. 31 Juan Martin del Potro in the second round and then stunned No. 2 Rafael Nadal in the next round, his first-ever match against a top-10 player. He then beat 42nd-ranked Adrian Mannarino in the quarter-finals before losing to No. 8 Alexander Zverev in the semis.

That roll made him the youngest player to ever to reach an ATP World Tour Masters 1000 semifinal.

After qualifying for the U.S. Open, he advanced to the second round of the main draw with a victory over Daniil Medvedev, then beat eighth seed Jo-Wilfried Tsonga. He dispatched Kyle Edmund next, becoming the youngest player to reach the fourth round of the tournament since Michael Chang in 1989.

“I didn’t expect to be this far along at this point in the season. My goal was to be ranked 150th (on the ATP Tour) by the end of the season,” said Shapovalov, who rose from No. 143 to 67th on Aug. 14 after the Rogers Cup and will rise even higher after his performance at the U.S. Open. “I thought that was a very good goal to have, tough but doable.”

Although his meteoric rise in August has been impressive, the number of matches Shapovalov has played may have taken their toll. He had eight aces to Carreno Busta’s one on Sunday, but the younger player also had 55 errors to the Spaniard’s 25. In particular, he struggled with his forehand and often needed two serves in the two-hour, 54-minute match.

Pablo Carreno Busta celebrates his win over Denis Shapovalov at the U.S. Open on Sept. 3.Clive Brunskill /
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Shapovalov blew a 5-2 lead in the first set. Carreno Busta saved three set points, cruised in the tiebreaker and then controlled the early part of the second set before Shapovalov rallied to force another tiebreaker. Shapovalov lost that set point on a forehand that went long.

Seemingly refocused after the break, Shapovalov raced out to a 3-0 lead in the third set. However, Carreno Busta broke back to win three straight games and tie it 3-3. Two more unforced errors by Shapovalov made it 5-5, with Carreno Busta’s consistency wearing down the emotional teenager.

Shapovalov took a one-game lead, but Carreno Busta forced the third tiebreak to push the match past the 2:45-mark — the longest ATP match Shapovalov has competed in his young career. The Canadian couldn’t handle Carreno Busta’s serve on match point.

Carreno Busta said he may not have even heard of his opponent until last month.

“He’s playing with a lot of confidence and he’s very young, so in the future, he will be one of the best,” said Carreno Busta.

Shapovalov hopes it won’t be the last time he’s in the U.S. Open, saying that his confidence has grown with each experience this summer.

“I’m just playing every match with the belief I have within myself,” he said. “I always wanted to play these guys and these matches, and it’s just a lot of fun to be on the court. I think that helps me in the matches.”